691357 has 4 divisors (see below), whose sum is σ = 721440. Its totient is φ = 661276.

The previous prime is 691349. The next prime is 691363. The reversal of 691357 is 753196.

691357 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 691357 - 2³ = 691349 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691337) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15007 + ... + 15052.

It is an arithmetic number, because the mean of its divisors is an integer number (180360).

2⁶⁹¹³⁵⁷ is an apocalyptic number.

It is an amenable number.

691357 is a deficient number, since it is larger than the sum of its proper divisors (30083).

691357 is a wasteful number, since it uses less digits than its factorization.

691357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30082.

The product of its digits is 5670, while the sum is 31.

The square root of 691357 is about 831.4788030972. The cubic root of 691357 is about 88.4234498234.

The spelling of 691357 in words is "six hundred ninety-one thousand, three hundred fifty-seven".